Asus HD 3850 512MB rebadged 3870??

rogue1979

Diamond Member
Mar 14, 2001
3,062
0
0
Picked this up on the $30 rebate deal, $62.37 shipped from Newbiz.com

Used CBABE to flash it to 840/2125 @1.3v.
Worked on overclocking the core mostly, can get 850 @ 1.327 but it runs cooler at 1.3v, 59C under full load with a VF900. That's crammed in an Ultra Microfly.

Thought the GDDR3 was stellar hitting 2125MHz, figured it was near the limit so I left it.

After a few days got motivated to push the memory clocks. Boy, what a big surprise!!!!!

I am now at 2400MHz on the ram, and I don't think there is anyway GDDR3 will hit that speed
at stock voltage. I have some nice copper ramsinks on it, but it has to be GDDR4.

Verified the clock speeds with ATItray tools and running 3Dmark06 (breaking 12K now).

Has anyone heard of any manufacturer putting GDDR4 on a 3850?

I figure it is more likely they had lots of 3870's unsold and just flashed it to a 3850, repackaged and sent it out the door.

Gonna try higher later, some people managed to get their 3870's to 2600MHz or more on the memory.


 

rogue1979

Diamond Member
Mar 14, 2001
3,062
0
0
Maybe I was being a bit over enthusiastic and/or premature.

2400MHz screwed up in COD4. Lowered to 2350MHz and it seems stable now.

Could it be possible for GDDR3 to hit these speeds with no voltage mods?
 

LordGestle

Senior member
Jan 2, 2001
764
0
0
Originally posted by: rogue1979
Picked this up on the $30 rebate deal, $62.37 shipped from Newbiz.com

Used CBABE to flash it to 840/2125 @1.3v.
Worked on overclocking the core mostly, can get 850 @ 1.327 but it runs cooler at 1.3v, 59C under full load with a VF900. That's crammed in an Ultra Microfly.

Thought the GDDR3 was stellar hitting 2125MHz, figured it was near the limit so I left it.

After a few days got motivated to push the memory clocks. Boy, what a big surprise!!!!!

I am now at 2400MHz on the ram, and I don't think there is anyway GDDR3 will hit that speed
at stock voltage. I have some nice copper ramsinks on it, but it has to be GDDR4.

Verified the clock speeds with ATItray tools and running 3Dmark06 (breaking 12K now).

Has anyone heard of any manufacturer putting GDDR4 on a 3850?

I figure it is more likely they had lots of 3870's unsold and just flashed it to a 3850, repackaged and sent it out the door.

Gonna try higher later, some people managed to get their 3870's to 2600MHz or more on the memory.
Check out what the pn# on the memory, mine had qimonda hyb18h512321bf-10 which is GDDR3.
 

rogue1979

Diamond Member
Mar 14, 2001
3,062
0
0
It's running on a 2180 @ 3.2GHz.

Unfortunately I used a small spot of epoxy smeared evenly to attach the ramsinks, I think it would be very difficult to try and remove, so they have to stay. So there is no way to tell what the numbers are on the ram anymore:(
 

AzN

Banned
Nov 26, 2001
4,112
0
0
GDDR3 hitting those speeds is not out of the question. 9800gtx uses gddr3 and hit that easily.
 

rogue1979

Diamond Member
Mar 14, 2001
3,062
0
0
Update:

After playing about a dozen or so of my favorite games I am now at the following speeds:

core 830MHz @ 1.275v - lowered from 840MHz @ 1.3v, trying to keep gpu under 60C
memory 2250MHz stock voltage

Load temps 59C with VF900 in modified Ultra Microfly case.

So the conclusion is that it is GDDR3.

Have tried several drivers and the Xtreme-G Catalyst 8.7 is the fastest. COD4 shows a big improvement with these drivers, 3Dmark06 is 11,600.

Lowered the voltage on the e2180 from 1.45v to 1.40v, went from 3200MHz down to 3150MHz, plenty fast for me. I like things to run cooler than necessary, which can be a bit of a challenge
in a cube case. Load temps are running about 60C.
 

apoppin

Lifer
Mar 9, 2000
34,890
1
0
alienbabeltech.com
Originally posted by: rogue1979
Update:

After playing about a dozen or so of my favorite games I am now at the following speeds:

core 830MHz @ 1.275v
memory 2250MHz stock voltage

Load temps 59C with VF900 in modified Ultra Microfly case.

So the conclusion is that it is GDDR3.

Have tried several drivers and the Xtreme-G Catalyst 8.7 is the fastest. COD4 shows a big improvement with these drivers, 3Dmark06 is 11,600.

Lowered the voltage on the e2180 from 1.45v to 1.40v, went from 3200MHz down to 3150MHz, plenty fast for me. I like things to run cooler than necessary, which can be a bit of a challenge
in a cube case. Load temps are running about 60C.
that is pretty good for 3850 and close to my own 4870 performance in 3DMark06

my core is 820 and my DDR5 can hit 1165 which is the upper limit of my OC'ing tool. All i had to do was increase the fan speed to 50% and heat is no longer an issue. i get 13334 in 3DMark06 with that setting and my e4300 @ 3.33Ghz. However, it appears to be very little over the more conservative settings of 790/1100 and my 4300@3.25Ghz which scores 13318.

i am settling on the milder OC which does not stress my system. Later, when i have x48's PCIe 2.0 and q9550 i will see what difference it makes
EDIT: that is an awesome OC for 3XX0 series; mine is 4000 series :Q
 

rogue1979

Diamond Member
Mar 14, 2001
3,062
0
0
Originally posted by: apoppin

that is pretty good for 3850 and close to my own 3870 performance in 3DMark06

my core is 820 and my DDR5 can hit 1165 which is the upper limit of my OC'ing tool. All i had to do was increase the fan speed to 50% and heat is no longer an issue. i get 13334 in 3DMark06 with that setting and my e4300 @ 3.33Ghz. However, it appears to be very little over the more conservative settings of 790/1100 and my 4300@3.25Ghz which scores 13318.

i am settling on the milder OC which does not stress my system. Later, when i have x48's PCIe 2.0 and q9550 i will see what difference it makes
Like you, I usually overclock to the max, make sure it is stable, and then back off with a slight decrease in voltage and speed for less stressful running.

If your overclocking tool limits your memory clocks you could use CBABE and flash whatever speeds you want to try. You could also give a slight bump in GPU voltage if needed. I bet the GDDR5 would run 2400-2500 easy (1200-1250) or possibly higher.

Seems like your cpu is more than maxing out the gpu. You 3Dmark06 score is about 15% faster than mine with the video cards at close to the same speed. I think this tells me that your 2MB L2 cache is definately giving you a boost over my 1MB L2 cache.

My idea is just to sit tight and wait for the e5200. I can get 2MB L2 cache, probably 4GHz on the same motherboard at only 320MHz fsb. It's a dirt cheap upgrade, only supposed to be $85 or so. Sell off my 2180 and just a few bucks invested.

 

JPB

Diamond Member
Jul 4, 2005
4,042
84
91
Originally posted by: apoppin
Originally posted by: rogue1979
Update:

After playing about a dozen or so of my favorite games I am now at the following speeds:

core 830MHz @ 1.275v
memory 2250MHz stock voltage

Load temps 59C with VF900 in modified Ultra Microfly case.

So the conclusion is that it is GDDR3.

Have tried several drivers and the Xtreme-G Catalyst 8.7 is the fastest. COD4 shows a big improvement with these drivers, 3Dmark06 is 11,600.

Lowered the voltage on the e2180 from 1.45v to 1.40v, went from 3200MHz down to 3150MHz, plenty fast for me. I like things to run cooler than necessary, which can be a bit of a challenge
in a cube case. Load temps are running about 60C.
that is pretty good for 3850 and close to my own 3870 performance in 3DMark06

my core is 820 and my DDR5 can hit 1165 which is the upper limit of my OC'ing tool. All i had to do was increase the fan speed to 50% and heat is no longer an issue. i get 13334 in 3DMark06 with that setting and my e4300 @ 3.33Ghz. However, it appears to be very little over the more conservative settings of 790/1100 and my 4300@3.25Ghz which scores 13318.

i am settling on the milder OC which does not stress my system. Later, when i have x48's PCIe 2.0 and q9550 i will see what difference it makes
4660 ? :shocked:
 

ASK THE COMMUNITY